Filter bag condition signal for vacuum cleaner

ABSTRACT

A vacuum cleaner appliance in which a warning signal to empty the filter bag is actuated by a predetermined temperature rise in the blower motor that is occasioned when the rate of flow of motor coolant air through the filter bag is reduced below a predetermined level.

United States Patent [1 1 Valbona et al.

[ 1 Oct. 23, 1973 FILTER BAG CONDITION SIGNAL FOR VACUUM CLEANERInventors: Bruno M. Valbona, Avon; Robert J. Emmons, Manchester; MauriceP. Samuelian, West Hartford, all of Conn.

Assignee: Dynamics Corporation of America,

New York, NY.

Filed? imi/T173371 Appl. No.: 200,627

Related U.S. Application Data Division of Ser. No. 83,300, Oct. 23,1970, Pat. No.

U.S. Cl. 15/339 Int. Cl. A471 5/00 Field ofSearch 15/339,412,413, 319,

References Cited UNlTED STATES PATENTS Owenmark 15/319 X Lagerstrom15/319 Vose 15/350 X Osborn 15/350 X Lindberg et al. 15/350 X Kent15/319 X Primary ExaminerJohn Petrakes Assistant Examiner-C. K. Moore31.- A Attorney-Watson D. Harbaugh et al.

ABSTRACT A vacuum cleaner appliance in which a warning signal to emptythe filter bag is actuated by a predetermined temperature rise in theblower motor that is occasioned when the rate of flow of motor coolantair through the filter bag is reduced below a predetermined level.

4 Claims, 8 Drawing Figures PATENTED UN 23 I975 SHEET 10F 2 r FIG. 3

PATENTEDUCI 23 I973 SHEET 2 0F 2 FIG. 5

FILTER BAG CONDITION SIGNAL FOR VACUUM CLEANER Valbona'et al., U.S. Pat.No. 3,667,084, parent of this application. Valbona et al., Pat. No.3,695,006, filed of even date herewith.

CROSS REFERENCES TO RELATED CASES CONSIDERATION OF INVENTION Theusefulness and effectiveness of a hand propelled lightweight vacuumcleaner is reflected in its ability to reach remote areas as underfurniture, and its short silhouette for packaging and storability insmall spaces. F urthermore, its all around adaptability to the comfortand stature of a user and long periods of use without tiring are ofimportance, it being desirable that throughout its major use the nozzleis maintained at a predetermined angle to the floor and that this resultbe accomplished somewhat automatically and comfortably by the distanceof the nozzle to the handle being adjusted so that the handle is closeto the natural level of the hand of the user to maintain saidpredetermined nozzle angle as a natural concomitant of the use of thecleaner. This angle is preferablyapproximately 45 to compromise vectorsof forces involved in pushing and pulling the nozzle across a carpet inconjunction with manually supporting the upper end of the sweeper sothat the body weight of the cleaner maintains an adequate but light andconstant pressure of the nozzle against the carpet. This is related alsoto the natural action of the user pushing with the handle loweredslightly and pulling with the handle raised slightly to rock the nozzlewith respect to a natural intermediate supported position. I

Moreover, by way of easing the manual effort of holding and manipulatingthe sweeper and the nozzle, particularly by relaxing the conventionaltightness of manually gripping the handle, the handle is curvedsubstantially 25 towards the horizontal and comprises a substantiallywide width helve over an oval opening through which the fingers of theuser can be crooked to propel the sweeper in eitherdirection withoutneed for gripping the helve portion of the handle. The crooked fingersmerely engage the shoulders defined by closed ends of the opening.

The housing is provided with a carrying handle located forwardly of thehelved handle for several purposes including bimanual manipulation ofthe sweeper and for the manipulation of two separable housing parts,namely the lower housing and latch assembly, and for holding the lowerhousing while replacing or cleaning the filter bag therein.

Other and further structural characteristics and objects will appearfrom the ensuing description of a preferred construction that islightweight, well balanced and adaptable for easy handling. -It iseconomical to make, use, and service, as well as readilypackaged orsotred in minimal space.

IN THE DRAWINGS FIG. 1 is a perspective view, partially from the rearshowing a preferred embodiment of the invention;

FIG. 2 is a side elevational view, partly cut away, of the embodiment inFIG. 1 showing its normal working orientation angle with respect to afloor and its length that is adjustable for persons of differentheights;

FIGS. 3 and 4 are sectional views taken on lines 3-3 and 4-4,respectively, in FIG. 2;

FIG. 5 is an elevational view of the lower end of the lower housingpartially cut away indicating the structural relationship of the intaketube and the filter bag mounting;

FIG. 6 is an elevational view of the upper housing secured to the upperend of the lower housing and partially cut away to show the blower andits relationship to the upper end of the'filter bag and its coolingarrangement and electrical controls;

FIG. 7 is a sectional view taken on line 7-7 of FIG. 6; and

FIG. 8 is a partially sectional view showing the mounting of the blowerand the circulation of the motor cooling air.

THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, the lightweightcleaner 10 embodying the invention comprises a lower housing 12compartmentized at 13 as a tank to receive loosely therein a ratherstiff walled porous filter bag 14. The filter bag is mounted on a holder11 and inserted to its working position through a full size opening 15at the upper end of the housing with its open end 17 disposeddownwardly, and the upper end of an intake tube 25 is received through aguide conduit 16 provided in the lower end of the housing 12 to extendupwardly into the open lower end 17 of the filter bag. Both the lowerend of bag and the upper end of the tube are supported in place by theguide conduit 16 and a metal cross plate 18 (FIG. 5).

The bag holder 11 comprises a ring 21 and a U- shaped bail 9 securedthereto for handling. The filter bag is inserted through the ring 21until it touches the bight at 27 of the bail. Then the edges of the bagare folded as at 19 externally back and around the ring 21. Thereupon,the assembled bag and holder are slid into the housing open end first.Drop out of the bag is accomplished by turning the housing with thenozzle end up. A urethane foam pad 23 interengages the conduit 16 andthe open folded end of the filter bag in sealing relationship.

The guide conduit 16 preferably extends as at 34 beyond the lower end ofthe housing 12 where it is threaded with a heavy thread 31 and has aninternal square shoulder 32 at the inner end of a terminal enlargement29 receiving a gland seal 28.

The intake conduit 16 slidably receives the tube 25 which terminallycarries a nozzle 20 by a connection 22 that permits a lateral swivellingof the nozzle, and, as indicated by broken lines 24 (FIG. 2), the tubeis adjustable as to its exposed length by means of a gland nut 26axially compressing the resilient gland seal 28 (FIG. 4) to expand itradially against the tube. The seal 28 is disposed between twoanti-friction metal washers 30 resting against oppositely facingshoulders. Shoulder 33 is on the gland nut 26 and the shoulder 32 is atthe inner end of the enlargement 29 within the threaded housingextension tube guide 34.

An upper housing 36, as also shown in FIG. 6, mates at its lower endwith the contour of the upper end of the lower housing where it is heldin alignment therewith by toggle latches 38 to close the upper end ofthe compartment 13 and hold the bag 14 in place by means of a removablepartition 40 having an outlet opening 42 therein covered by a fine wirescreen 43. The air is withdrawn from the filter bag compartment 13through the wire screen 43 by a centrifugal blower (FIG. 8).

The blower comprises an air impeller 44 having radial blades 45 disposedon a supporting plate 47 on the side of the opening 43 so that thepartition 40 serves as a shroud for the blades and redirects the exhaustaxially as indicated by the arrows in FIG. 6. The impeller is mounted onthe motor shaft 46 by a nut and lock nut assembly 48 as driven by amotor 50 having a rotor and stator. These motor parts are disposed in ahousing 52 having bearing support spiders 51 at opposite ends whichestablish a path for the flow of air through these parts.

The blower and motor are mounted in operative position on an imperviousbaffle partition 54 (FIG. 6) which compels air exhausted by the blowerfrom the filter bag compartment to flow peripherally through the exhaustarea 53 and then through the support spiders 51 and through thecooperating armature and stator elements to cool them before beingexpelled through the grating 56 at the upper end of the upper housing.

The grating 56 is shaped to provide parallel grill elements 55 spaced adistance adequate to receive loops 57 of an electrical extension cord 59therebetween with a slight squeezing action to hold the loops in placeeither with or without the cooperation of the projection 61 at the otherend of the housing providing a cleating action. The cord 59 can be woundcircularly as shown in FIG. 1 or wound in a figure 8 (not shown) toavoid any twist tangling of the cord.

Extending beyond the upper housing is a handle section 60 securedthereto by assembly screws 62. The handle can be made in matchinghalves, but preferably, as shown, one portion is'made as a base portion63 that is deeply recessed and open to receive the wiring and wire nutsthat connect a main switch 64, a surge switch 66 and a warning light 68in circuit with the motor as more particularly described in said Valbonaet al application, reference to which is hereby made. It is sufficientto mention at this time that the main switch 64' provides two regularspeeds HI and LO while the surge switch 66 must be hand held to overridethe main switch to provide a higher or surge speed for momentaryoperation.

A thermostat 70, in heat exchange contact with the stator core 67 of themotor, is responsive to the temperature of the motor and closes to warnof a high temperature by energizing the red warning light 68 to indicatethat the bag should be emptied because not enough air is getting throughthe filter bag to adequately cool the motor. Thus, the warning light 68indicates when the motor becomes too warm and also that the filter bagrequires emptying for efficient vacuuming operation.

The switch 64 is preferably a three position switch for OFF, L and HIoperation while the switch 66 preferably is a spring returned pushbutton or slide switch which requires sustained manual operation toremain ON. The switch 66 is located at the top of the handle section 60where it is remote enough to require some hand effort to hold it ON withlittle likelihood that it will be held on throughout continuous manualoperation of the cleaner, but rather only when a particular vacuumingpick-up difficulty is presented.

Once the electrical switch and light components are conventionallymounted and the wiring is located in place, a cover plate 69 is securedin place to the base member 63 with the extension cord strain reliefelement 65 disposed as shown in FIG. 1.

As already mentioned in the objects, the handle is shaped for particularusefulness in coaction with the adjustable distance between the nozzleand the handle with respect to the floor 71 (FIG. 2), as held by usersof different statures at an angle to the floor of substantially 45. Thehandle is formed and inclined away from this angle of 45 approximately25 thereto. This relationship is maintained throughout all adjustmentsas to height so that any one of a great majority of users, whenstanding, need only manipulate the sweeper at a level which is thenatural position of the hand at the users side.

To assure optimum comfort of hand position and sweeper operation, thehelve portion 72 is provided with rounded ends or shoulders 74 for thecrooking of the users fingers therebetween. Then the fingers engage oneor the other shoulder for push and pull movements without need forgripping the helve anymore than to retain it in the crooked fingers.Thus the wrist of the user is not strained as when a tight grip of aconventional sweeper handle is required of the user. Even with thepresent invention such a habitual tight grip is relieved of strain somuch that the user gradually relaxes in comfort with the ease ofoperation. It is preferred to connect the lower ends of the shoulders 74to prevent them catching on articles. Moreover, the ultimate appearanceis also improved as well as the avoidance of sharp corners and edges.

As shown in FIGS. 1 and 2 a second or carrying handle 76 for the cleaneris located on the lower housing 12. It is of a length and so locatedthat a person can pick up the cleaner 10 above its center of gravity forcarrying, or both handles 60 and 76 can be used by both hands of theuser to sweep other than horizontally disposed objects.

The construction of the nozzle 20 also adds to the ease and user comfortof operation when rocking the nozzle by lowering the handle whilepushing it and raising the handle while pulling it under certainsweeping conditions. The level of the brush is controlled by a footoperated cam that centrally raises and lowers it in vertical tracks 77at the ends of the nozzle as urged downward by compression springs 79for resilient engagement of the brush with a work surface under theweight of the cleaner. This brush can be raised by the cam 73 beingmoved longitudinally to raise the brush so that its lower edge is at orabove the level of the edges of the mouth of the nozzle. The cam can befoot or finger operated by buttons 80 on carrier arms 82 secured to thecam. Furthermore, three spaced oval shaped rollers 81 (FIG. 1) arejournalled within the mouth of the nozzle to extend a short distancetherebelow to carry the weight of the sweeper on hard floorin g.

It will be further appreciated that various cleaning attachments can beprovided for the sweeper and used interchangeably with the nozzlecarrying tube 25 including a flexible hose merely by loosening the glandnut 26, removing the tube 25, inserting a like tube carrying anothercleaning attachment, and retightening the gland nut. If there is anysubstantial length provided for the tube, the tube can be adjusted as toits exposed length the same way as already described since the tube isof uniform size throughout and the tube can have measuring indicia on itif the adjusted exposed length of the tube is critical beyond thedesires of the user. In fact, to assist users in readily adjusting thenozzle carrying tube 25 to their statures, personalizing height marks 85are provided on the tube 25 every 1.50 inches approximately, and can berelated to every 2 inches of stature height within a general range ofuser statures which will provide approximately the proper handle heightfor the level of the users hand which is one-half the stature height.The range accommodated thereby is quite wide because the marked tube 25has clearance in the filter bag to telescope more than 1 foot and thisprovides a stature range that is over 16 inches. These marks and thegland nut position are so arranged that when one of the marks is at thefront edge of the gland nut, as shown in FIG. 4, the adjacent highermark is not located at the seal 28. Accordingly, the marks can berecessed into the external surface of the tube without any possibilityof air leaking past the seal. Otherwise, the tube 25, preferably beingmade of plastic, can have the recesses filled with a plastic filler of acontrasting color. The number and arrangement of the marks are thendesign free of possible physical requirements.

The nozzle, 20, the housing 12 and 36, the gland nut 26, and the tube 25are preferably for lightness, strength and durability made of a plastictaken from the following group of plastics: Y

polyester resins;

rigid vinyls;

styrene polymers;

acrylics;

polyvinyl chlorides;

acrylic-PVC alloys; and A B S resins such as:

styrene-acrylonitrilebutadiene tetrapolymers Having thus described thepreferred embodiments with explanation of the concepts involved, it willbe understood how various and further embodiments can be made withoutdeparting from the spirit of the invention.

What is claimed is:

1. In a lightweight vacuum cleaner the combination of a portable housinghaving a sealed filter bag compartment subjected to subatmosphericpressures,

conduit means including an intake nozzle at one end and discharging atthe other end into said compartment at the lower end thereof,

means defining an end wall for the compartment and including a sealingmember around said conduit,

a proous walled filter bag received in said compartment with its openend disposed in sealing engagement against the sealing member aroundsaid conduit,

an electric motor and blower means with its intake in sealedcommunication with said compartment outside of said filter bag towithdraw air from said compartment,

exhaust means for conducting withdrawn air as a coolant through theelectrical motor, and temperature responsive means contacting saidelectric motor in heat exchange relationship to give a signal related toa predetermined temperature of the motor reached when the flow rate ofwithdrawn air passing through the motor is insufficient to cool themotor below said predetermined temperature thus indicating anundesirable condition of the filter 6 bag. 2. In a lightweight vacuumcleaner, the combination of,

a housing having a filter bag compartment,

a nozzle conduit opening into one end of the compartment,

a filter bag removably secured in said compartment in sealedcommunication interiorly with said nozzle conduit,

a blower means in sealed communication with said compartment exteriorlyof said filter bag to establish an air pressure differential across thewall of the filter bag in the compartment including,

an impeller withdrawing air from said compartment outside of said filterbag,

an electric motor dirving said impeller, and

means for passing air withdrawn from said compartment in heat exchangecontact with the stator of said motor to cool it,

temperature responsive means in heat exchange relationship with saidmotor stator core to to be energized at a predetermined temperaturethereof, and

signal means actuated by said energization of said temperatureresponsive means to indicate when flow of coolant air through filter bagfor motor is impaired to the point the filter bag should be attended tofor improving its operating efficiency.

3. The combination defined in claim 2, in which said electric motor hasforaminatedbearing supporting housing end members, and

baffle means for directing the flow of air progressively over a portionof the outer surface of the housing and sequentially through theinterior of the motor housing.

4. In a lightweight vacuum cleaner, the combination a plastic housinghaving a filter bag compartment,

a plastic nozzle conduit opening into one end of the compartment,

a stiff porous filter bag means removably secured in said compartment insealed communication interiorly with said nozzle conduit including aresilient ring around the mouth of the bag over which the bag edge isfolded back upon itself,

a blower means in sealed communication with said compartment exteriorlyof said filter bag to establish an air pressure differential across thewall of the filter bag in the compartment including,

an impeller withdrawing air from said compartment outside of said filterbag,

an electric motor with a variable working temperature driving saidimpeller,

means for passing air withdrawn from said compartment in heat exchangecontact with the stator of said motor to cool it,

temperature responsive means in heat exchange relationship with saidmotor stator core, and

signal means actuated by said temperature responsive means at apredetermined temperature, occasioned by a substantial reduction of theflow rate of air coolant through the filter bag means to indicate anefficiency reduced condition of the filter bag.

1. In a lightweight vacuum cleaner the combination of a portable housinghaving a sealed filter bag compartment subjected to subatmosphericpressures, conduit means including an intake nozzle at one end anddischarging at the other end into said compartment at the lower endthereof, means defining an end wall for the compartment and including asealing member around said conduit, a porous walled filter bag receivedin said compartment with its open end disposed in sealing engagementagainst the sealing member around said conduit, an electric motor andblower means with its intake in sealed communication with saidcompartment outside of said filter bag to withdraw air from saidcompartment, exhaust means for conducting withdrawn air as a coolantthrough the electrical motor, and temperature responsive meanscontacting said electric motor in heat exchange relationship to give asignal related to a predetermined temperature of the motor reached whenthe flow rate of withdrawn air passing through the motor is insufficientto cool the motor below said predetermined temperature thus indicatingan undesirable condition of the filter bag.
 2. In a lightweight vacuumcleaner, the combination of, a housing having a filter bag compartment,a nozzle conduit opening into one end of the compartment, a filter bagremovably secured in said compartment in sealed communication interiorlywith said nozzle conduit, a blower means in sealed communication withsaid compartment exteriorly of said filter bag to establish an airpressure differential across the wall of the filter bag in thecompartment including, an impeller withdrawing air from said compartmentoutside of said filter bag, an electric motor driving said impeller, andmeans for passing air withdrawn from said compartment in heat exchangecontact with the stator of said motor to cool it, temperature responsivemeans in heat exchange relationship with said motor stator core to beenergized at a predetermined temperature thereof, and signal meansactuated by said energization of said temperature responsive means toindicate when flow of coolant air through filter bag for motor isimpaired to the point the filter bag should be attended to for improvingits operating efficiency.
 3. The combination defined in claim 2, inwhich said electric motor has foraminated bearing supporting housing endmembers, and baffle means for directing the flow of air progressivelyover a portion of the outer surface of the housing and sequentiallythrough the interior of the motor housing.
 4. In a lightweight vacuumcleaner, the combination of, a plastic housing having a filter bagcompartment, a plastic nozzle conduit opening into one end of thecompartment, a stiff porous filter bag means removably secured in saidcompartment in sealed communication interiorly with said nozzle conduitincluding a resilient ring around the mouth of the bag over which thebag edge is folded back upon itself, a blower means in sealedcommunication with said compartment exteriorly of said filter bag toestablish an air pressure differential across the wall of the filter bagin the compartment including, an impeller withdrawing air from saidcompartment outside of said filter bag, an electric motor with avariable working temperature driving said impeller, means for passingair withdrawn from said compartment in heat exchange contact with thestator of said motor to coOl it, temperature responsive means in heatexchange relationship with said motor stator core, and signal meansactuated by said temperature responsive means at a predeterminedtemperature, occasioned by a substantial reduction of the flow rate ofair coolant through the filter bag means to indicate an efficiencyreduced condition of the filter bag.